found: Work cat.: 2001440775: Bielitz, M. Hexachord und Semantik, 1998.
found: Grovemusic.com WWW site, Sept. 26, 2003(Hexachord: A term denoting a series of six notes ascending stepwise through two whole tones, a semitone and two further whole tones, used as a complement to the eight-note diatonic system (including B-flat and B-natural) in the teaching of practical music and music theory, and thus in composition (particularly in the later period), from the Middle Ages to the 17th century)
found: New Harvard dict. mus.
found: Oxf. comp. mus., 2002.
found: Baker's dict. mus.
found: Web. 3.